Initiated: February 9, 1909, Belton Lodge No. 450, Belton, Missouri.
In 1911, several Members of Belton Lodge separated to establish Grandview Lodge No. 618, Grandview, Missouri, and Brother Truman served as its first Worshipful Master. At the Annual Session of the Grand Lodge of Missouri, September 24-25, 1940, Brother Truman was elected (by a landslide) the ninety-seventh Grand Master of Masons of Missouri, and served until October 1, 1941. Brother and President Truman was made a Sovereign Grand Inspector General, 33&deg, and Honorary Member, Supreme Council on October 19,1945 at the Supreme Council A.A.S.R. Southern Jurisdiction Headquarters in Washington D.C., upon which occasion he served as Exemplar (Representative) for his Class. He was also elected an Honorary Grand Master of the International Supreme Council, Order of DeMolay. On May 18, 1959, Brother and Former President Truman was presented with a fifty-year award, the only U.S. President to reach that golden anniversary in Freemasonry.